Railway car



g- 30, 1966 D. w. ROLLINS 3,269,779

RAILWAY CAR Filed Nov. 2, 1964 5 Sheets-Sheet 1 FIG.

INVENTOR. DALLAS W. ROLLINS ATTORNEY 0, 1966 D. w. ROLLINS 3,269,779

RAILWAY CAR Filed Nov. 2, 1964 5 Sheets-Sheet 2 FIG.4.

INVENTOR. DALLAS W. ROLLINS igwhm ATTORNEY Aug. 30, 1966 D. w. ROLLINS RAILWAY CAR 5 Sheets-Sheet 5 Filed Nov. 2, 1964 ATTORNEY Aug. 30, 1966 0. w. ROLLINS RAILWAY CAR 5 Sheets-Sheet 5 Filed Nov. 2, 1964 INVENTOR. DALLAS W. ROLLINS BY ATTORNEY United States Patent 3,269,779 RAILWAY CAR Dallas W. Rollins, St. Charles, Mo., assignor to ACF Industries, Incorporated, New York, N.Y., a corporation of New Jersey Filed Nov. 2, 1964, Ser. No. 408,002 11 Claims. (Cl. 302-52) This invention relates to railway cars and more par ticularly to a covered hopper railway car adapted to withstand a positive internal pressure.

Normally, pressurized railway cars are formed of a cylindrical shape which is the ideal shape for a pressure vessel or pressurized railway car from a structural viewpoint. However, cylindrical vessels or shells are not well suited for high capacity designs as the only practical way to increase the volumetric capacity of a cylindrical shell is to lengthen the shell. However, due to railroad restrictions, as the length is increased beyond certain limits the diameter must be decreased so that to achieve volumes comparable to those desired, a much longer shell is required which also requires additional hatches and outlets and is excessively heavy.

In addition to the width restrictions imposed on railway cars there is a restriction on the maximum height of the center of gravity in a fully loaded railway car. With a true cylindrical shape, the vertical position of the shell is limited since the lower surface thereof must be above the center sill of the understructure. Thus, for large capacity railway cars loaded with a high density lading, the loaded center of gravity will be relatively high and possibly exceed the permissible height above the rails.

The above limitations of a cylindrical shell for a railway car have been somewhat overcome by railway tank car builders by departing from a true cylindrical shape with a fish-belly design in which the center portion of the shell is located at an elevation lower or closer to the rails than the end portions. However, in this design, an elaborate transition section must be provided adjacent each end portion of the shell where the cross section is reduced. Additionally, to achieve proper unloading of most bulk lading, steep angular slopes are required to facilitate the lading flow. This necessitates the addition of internal false sheets and partitions which add to the weight and cost of the railway car.

The present invention comprises a railway hopper car having a circular upper shell struck from a single constant radius and joined tangentially along its lower edges to fiat sheets which receive stresses from the internal pressure and also act as slope sheets to facilitate lading discharge. Bottom discharge pneumatic outlets are arranged centrally of the width of the railway car .to pneumatically unload finely-divided particles. With this construction, a substantial amount of lading is carried in the center of the railway car closely adjacent .the rails thereby permitting a relatively short, high capacity railway hopper car with a relatively low loaded center of gravity. The volume of the railway car may be varied by increasing the length of the shell and incorporating additional discharge outlets. In addition to varying the length of the shell, the height and volume of the hopper car may be varied by varying the height of the juncture of the flat side sheets with the circular sheet.

The flat side sheets are arranged tangentially to the circular upper shell to receive stresses from the upper shell and are restrained against outward bulge at their upper edges by longitudinally extending chord members at the juncture of the side sheets with the upper circular she-ll. Side sills are arranged adjacent the lower edges of the flat side sheets to reinforce the side sheets against in 3,259,779 Patented August 30, 1966 ice terna-l pressures. Thus, stresses from internal pressure are transmitted primarily from the upper shell and the flat side sheets to the side sills and longitudinal chord members. The longitudinally extending chord members extend parallel to the side sills at the juncture of the side sheets with the upper circular sheet and aid in transmitting stresses from the upper circular shell to the flat side sheets. I

It is an object of the present invention .to provide a covered hopper railway car designed to withstand a positive internal pressure of a predetermined maximum and adapted to pneumatically unload finely-divided material.

A further object of the present invention is to provide a covered hopper railway car for pneumatically unloading finely-divided material and having a high volumetric capacity with a relatively low center of gravity while designed to withstand a positive internal pressure.

An additional object of this invention is the provision of a railway hopper car designed to withstand a positive internal pressure and having a plurality of bottom pneumatic outlets arranged centrally of the width of the car.

Another object is the provision of a method of fabricating in a minimum of steps a railway covered hopper car having an arcuate or circular shell and adapted to withstand a positive internal pressure.

The invention accordingly comprises the constructions hereinafter described, the scope of the invention being indicated in the following claims.

In the accompanying drawings, in which one of various possible embodiments of the invention is illustrated,

FIGURE 1 is a side elevation of the railway covered hopper car embodying the present invention and designed to withstand a positive internal pressure;

FIGURE 2 is an end elevation of the railway covered hopper car shown in FIGURE 1;

FIGURE 3 is a transverse section of the railway car shown in FIGURES 1 and 2 taken through a bottom outlet;

FIGURE 4 is an enlarged partial elevation of the railway covered hopper car with certain parts broken away;

FIGURE 5 is a section taken generally along line 55 of FIGURE 4 and showing the bolster structure;

FIGURE 6 is a top plan of a hopper with the bottom outlet removed from the hopper;

FIGURE 7 is an end elevation of the hopper shown in FIGURE 6;

FIGURE 8 is a side elevation of the hopper shown in FIGURES 6 and 7;

FIGURE 9 is a top plan of the bottom outlet removed from the railway car;

FIGURE 10 is a section taken generally along line 10-10 of FIGURE 4; and

FIGURE 11 is a schematic of the piping system for the railway covered hopper car illustrated in FIGURE 1.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Referring now more particularly to FIGURES 1-4, a railway hopper car is generally designated 10 and includes a shell designated 12. A truck 14 at each end of car 10 supports shell 12. Ladin'g comprising finelydivided particles or materials, such as, plastic pellets, flour, cement, phosphate, kaolin, and the like, is loaded throng-h hatch covers 16 from the top of the car. The lading is unloaded pneumatically from a plurality of bottom hopper structures generally designated 18 arranged centrally of the width of the car 10.

Referring to FIGURES 4 and 5, a hat-shaped stub center sill is indicated at 22 and is adapted to receive a conventional coupler and draft gear assemlbly (not shown). Secured over center sill 22 is a shear plate 24.

A bolster structure generally designated 26 has a bottom cover plate 27 and vertical webs 28. Shear plate 24 forms the upper cover plate for bolster structure 26. A center plate 29 secured to lower cover plate 2 7 is adapted to receive a kingpin on the associated truck 14. The other opposite end of car 10 is arranged similarly.

Referring to FIGURE 3, a side sill .generally designated 30 extends along each side of car 10. Shell 12 includes an upper circular shell portion 31 struck from radius R about point P and terminating in spaced lower edges 34. A flat side sheet 32 forms a lower flat portion of shell 12 on each side of car 10 and is arranged tangentially to upper circular portion 3 1. Each side sheet 32 has an upper edge in abut-ting relation to the superjacent lower edge 34 of upper portion 31. A channel 36 on each side of car 10 spans the adjacent juncture of upper circular portion 3 1 with side sheets 32 and extends in a generally parallel relation to side sills 30 for the length of shell 12. Channel 36 comprises an upper leg 37 secured to upper circular portion 3-1 and a lower leg 38 secured to side sheet 32 thereby to aid in transmitting stresses from upper circular portion 31 to side sheets 32. It is to be understood that shell 12 may be formed of a single sheet, if desired, instead of separate flat side sheets 32 welded to upper circular portion 3 1.

Each side sill 30 has respective upper and lower flanges 40 and 42 arranged in parallel relation to adjacent side sheet 32 and welded thereto. End slope sheets 44 extend between opposite sides of upper circular portion 31 and flat side sheets 32. Partial vertical bulkheads 46 extend between flat side sheets 32 as shown in FIGURE 4. Reinforcing gusset mernlbers 47 are secured to the outer surface of each end slope sheet 44 and extend between shear plate 24 and the adjacent end slope sheet 44 at each end of car 10. Secured t and extending between gusset members 47 are end bulkheads 48.

Each hopper structure 18 is identical and includes a hopper generally designated 49 and a bottom discharge outlet generally designated 50 secured to the bottom of hopper 49. Referring to FIGURES 6, 7 and 8, hopper 49 funnels from a generally rectangular upper opening -2 to a generally elliptical lower opening 54. End hopper sheets 56 and side hopper sheets 58 slope downwardly to lower opening 54. Sheets 56 and 58 are flat sheets and are secured, such as by welding, to curvilinear corner portions 60. Each hopper 49 is preassembled and inserted between fiat side sheets 32 with the upper mar ginal portions of side hopper sheets 58 lapping side sheets 32 and welded thereto adjacent side sills 30. End hopper sheets 56 are welded to end slope sheets 44 and partial bulkheads 46. Angle 62 forms an outwardly extending flange 64 adjacent the bottom of hopper 49. Bottom discharge outlet 50 has an upper circumferential flange 66 secured, such as by welding, to flange 64. Housing 68 of outlet 50 has surfaces sloping downwardly to a bottom discharge opening 70. Extending generally at a right angle to opening 70 is a discharge conduit 72. As side sheets 32 and hopper sides 58 are in the same plane and arranged at an angle of around 60 with respect to the horizontal, a relatively steep slope is provided which aids in the pneumatic discharge of the lading and permits a relatively high capacity car. To reinforce shell 12 adjacent partial vertical bulkheads 4 6, a box-shaped reinforcing member 69 extends about the interior of shell 12 as shown in FIGURES 4 and and comprises a boxed channel. Member 69 is welded along its lower end to adjacent hopper end sheets 56.

Car 10 is especially designed to withstand an internal pressure of around pounds per square inch (p.s.i.). To pressurize car 10 and to aerate the lading being discharged from conduit 72, a plurality of air inlets 74 are provided in housing 68. A gas permeable wall 76 consisting of a gas permeable fine mesh of metal, silk, plastic material or the like, preferably supported on a perforated rigid support is placed over each air inlet 74 to permit air to enter the interior of car 10 while preventing entry of the particles being discharged into inlets 74. A manifold 78 connects inlet nipples '80 leading to inlets 74.

To supply air to manifolds 78 and nipples 80 as shown in FIGURE 11, an air supply pipe 82 extends transversely of car 10 and has a cap 84 on each end thereof to permit connection to an air source (not shown) from either side of car 10. An air inlet pipe 83 extends along the car and a check valve 86 is provided between inlet line 83 and each manifold 78. Check valve 86 restricts the flow of air from car 10 to pipe 83 to maintain pressure within the car. Further, check valve 86 may be provided with a suitable manually actuated closure to block the flow of air in both directions. A lading discharge pipe 88 is connected to air supply pipe 82 and a valve 90 is manually movable between open and closed position to control the discharge of finely-divided material from pipe 88. A suitable discharge hose (not shown) may be connected to the end of pipe 88 opposite valve 90 for removal of the lading to a suitable storage bin or the like. A manual discharge valve 92 for each outlet 50 selectively controls discharge of lading from the respective outlet.

To prevent internal pressure within car 10 from exceeding a predetermined maximum amount, such as 15 p.s.i., one of the box type reinforcing members 69 as shown in FIGURE 3 has air inlet openings 94 adjacent the upper portion thereof. A suitable pressure relief valve 96 communicates with member 69 through a T 98 and is actuated at a predetermined pressure, such as 15 p.s.i., to provide a pressure relief. In the event it is desired to manually release the internal pressure, a manually operable valve 100 is provided adjacent an opposite end of T 98 to bleed the air from the interior of the car.

A vacuum relief valve 102 also communicates with reinforcing member 69 and upon a sub-atmospheric pressure existing within the car, valve 102 will open to permit air to be drawn within car 10. A suitable filter or the like may be provided adjacent relief valve 102 to prevent the entry of dirt and the like within the interior of the car.

Referring to FIGURES 3 and 4 an additional safety feature is shown comprising a hollow tie rod or bar 104 extending between opposite sides of shell 31 generally over the center of each outlet 50. End portions 106 of the bar 104 communicate with atmosphere and in the event of failure of a tie 104 interiorly of pressurized car 10, air is released through end portions 106 to atmosphere causing an audible signal which indicates a defective tie rod.

Operation is as follows:

One of the caps 84 is first removed from a selected end of air supply pipe 82 and a source of air is connected thereto with valve 90 being closed. A suitable hose or the like is connected to the discharge end of lading discharge pipe 88 for receiving the lading from car 10 and conveying it to a suitable bin or the like. Air enters the interior of car 10 through manifold 78 and air inlets 74 thereby aerating the lading within bottom outlet 50 and the interior of the car. When a pressure of around 15 p.s.i. is reached within the car, valve 90 is opened to permit the flow of air through discharge pipe 88 with valves 92 being closed. Valve 92 from a selected bottom outlet 50 to be unloaded is then opened and the lading therein is unloaded. Then, the next valve 92 is opened upon closing of the valve in outlet 50 which has been unloaded. In this manner, the bottom outlets 50 are successively unloaded until car 10 is unloaded.

Railway car 10 has been especially designed to withstand a positive internal pressure and yet is a large capacity car with a relatively low loaded center of gravity. Shell 12 includes side sheets 32 arranged tangentially with respect to upper arcuate portion 31 so that the lading slides easily along side sheets 32 into bottom outlets 50. The lading is aerated to aid in the pneumatic discharge by pushing of the finely-divided particles from the interior of the railway car.

In the method of assembly or fabrication of car 10, shell 12 may be formed by rolling a flat sheet between opposed rollers in one continuous operation. When desired to form shell 12 in such manner, the opposed rollers are first spaced from each other a sufficient distance to permit fiat end portions to be inserted between the rollers without being rolled thereby to form flat side sheet 32. Then the opposed rollers are adjusted to exert pressure on the flat sheet and the rolling operation is effected to form arcuate upper section 31. Thus, shell 12 is formed from a single continuous fiat sheet. Next, side sills 30 and chord members 36 are welded along outer surface of shell 12. End slope sheets 44 and partial bulkheads 46 are next secured to shell 12. In order for hoppers 49 to fit between side sills 3ft, hoppers 49 are preassembled into two portions of substantially the same dimensions. The two portions are then inserted between the side sills with adjacent sections of slope sheets 56 overlapping or mating so that the portions may be welded together along seams 51 to form hoppers 49. As hoppers 49 are inserted and moved downwardly into tight lapping relation with adjacent side sheets 32, close tolerances in the fabrication of hoppers 49 are not essential. Bottom outlets 50 are then welded to the undersides of hoppers 49.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results obtained.

As various changes could be made in the above constructions and methods without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A railway covered hopper car for pneumatically unloading finely-divided material and adapted to withstand a positive internal pressure, comprising an end stub center sill adjacent each end of the car, a side sill extending along each side of the car for substantially the entire length thereof, an intermediate chord member on each outer side of the car extending generally the length of the car in a direction generally parallel to the adjacent side sill, each of the chord members being spaced above the adjacent side sill, a plurality of transverse partitions spaced along the length of the car and dividing the car transversely into a plurality of hopper compartments, a lower side sheet on each side of the car extending between and secured to the adjacent side sill and the adjacent intermediate chord member, each lower side sheet being flat and sloping inwardly from the adjacent chord member to the adjacent side sill to provide a relatively smooth sloping inner surface along which the finely-divided material may flow for unloading, a bottom hopper outlet structure for each hopper compartment secured between the side sills generally centrally of the width of the car into which the finely-divided material fiows for unloading, said bottom outlet structure having opposed side outlet slope sheets secured to the adjacent side sills and forming a continuation of the superjacent lower side sheets, and an upper shell having spaced lower edges secured to the respective adjacent intermediate chord members adjacent the upper edges of the respective adjacent lower side sheets, said upper shell being arcuate with the lower side sheets positioned substantially tangentially to the radius of the shell adjacent the side sheets whereby forces are transmitted from the upper shell to the adjacent lower side sheets, and a pneumatic conduit connected to the bottom outlet structures for pneumatically unloading finely-divided material from the railway car.

2. A railway covered hopper car for pneumatically unloading finely-divided material and adapted to withstand a positive internal pressure comprising an end stub center sill adjacent each end of the car, a side sill extending along each side of the car for substantially the entire length thereof, an intermediate chord member on each outer side of the car extending generally the length of the car in a direction generally parallel to the adjacent side sill, each of the chord members being spaced above the adjacent side sill, a plurality of partitions spaced along the length of the car and dividing the car transversely into a plurality of hopper compartments, each of said partitions terminating upwardly generally at said intermediate chord members and extending generally vertically between the chord members and the side sills transversely of the car, a lower side sheet on each side of the car extending between and secured to the adjacent side sill and the adjacent intermediate chord member, each lower side sheet being flat and sloping inwardly from the adjacent chord member to the adjacent side sill to provide a relatively smooth sloping inner surface along which the finely-divided material may flow for unloading, a bottom hopper outlet structure for each hopper compartment secured between the side sills generally centrally of the width of the car into which the finely-divided material flows for unloading, said bottom outlet structure having fiat opposed outlet side slope sheets secured to the respective adjacent side sills and forming a continuation of the superjacent lower side sheets, an upper shell having spaced lower edges secured to the respective adjacent intermediate chord members and in generally edge-toedge relation to the adjacent lower side sheets, said shell being struck from a single uniform radius to form the shell of a uniform curvature with the lower side sheets positioned generally tangentially to the radius of the shell adjacent the side sheets whereby forces are transmitted between the shell and the adjacent lower side sheets, means to permit pressurizing the interior of the car, and pneumatic means connected to each of the bottom outlet structures for pneumatically removing the finely-divided material.

3. A covered hopper railway car as set forth in claim 2 wherein said means to permit pressurizing the interior of the car comprises at least one pneumatic inlet for each bottom outlet structure including an air permeable wall adjacent the finely-divided material to be unloaded.

4. A covered hopper railway car adapted to be pressurized comprising, an end stub center sill adjacent each end of the car, a side sill extending along each side of the car for the length thereof, an intermediate side chord member on each outer side of the car extending longitudinally generally the length of the car at a height generally around one-half the total height of the railway car, a shell between the side sills and chord members including an arcuate upper portion and a lower end portion on each side of the arcuate upper portion, each lower end portion being fiat and sloping inwardly from its associated chord member to provide a relatively smooth sloping inner surface along which finely-divided material may flow for unloading, said upper arcuate portion being struck from a single constant radius and the lower end portions being positioned tangentially to said radius, a bottom hopper outlet structure secured to the side sills and positioned centrally of the width of said oar whereby finely-divided material to be unloaded flows along the lower end portions to a position generally centrally of the width of the car, means to permit pressurizing the interior of the car to a predetermined maxirnunm pressure, and means operatively connected to the outlet structure to pneumatically remove the finely-divided material.

5. A covered hopper railway car as set forth in claim 4 wherein said outlet structure includes a bottom outlet having a generally elliptical outer contour and a generally central bottom opening for discharge of the finelydivided material, said opening being surrounded by funneling inner surfaces leading thereto with the finely-divided material flowing along the funneling inner surfaces to said central opening for discharge.

6. A covered hopper railway car as set forth in claim wherein the opening in said outlet structure leading to the outlet is generally elliptically shaped with the major axis thereof extending transversely of the car to provide a relatively large volumeric capacity in the outlet structure.

7. A covered hopper railway car as set forth in claim 4 wherein said bottom hopper outlet structure comprises a hopper having a generally rectangular upper opening and a transition section leading to a lower generally elliptical opening, and a bottom outlet beneath said generally elliptical opening to receive finely-divided material from the hopper, said means for pneumatically removing the finely-divided material being connected to the bottom outlet.

8. A covered hopper railway car adapted to be pressurized comprising an end stub center sill adjacent each end of the car, a side sill extending along each side of the car for the length thereof, an intermediate side chord member on each outer side of the car extending longitudinally generally the length of the car at a height generally around one-half the total height of the railway car, a lower side sheet on each side of the car secured between the adjacent side sill and the adjacent intermediate chord member, each lower side sheet being fiat and sloping inwardly from its associated chord member to provide a relatively smooth sloping inner surface along which finely-divided material may flow for unloading, an arcuate upper shell having space-d lower marginal portions secured to the intermediate chord members adjacent the lower side sheets, a hopper secured to the side sills and positioned centrally of the width of said car, said hopper having a generally rectangular upper opening and surfaces funneling to a lower generally elliptical opening, a bottom outlet secured beneath the hopper and having a generally elliptical upper opening aligned with said lower elliptical opening, said bottom outlet having a central bottom discharge opening surrounded by funneling inner surfaces leading from the upper elliptical opening with the finely-divided material flowing along the funneling inner surfaces to the central opening for discharge, means to permit pressurizing the interior of the car, and a pneumatic conduit connected to the bottom discharge opening for pneumatically removing the finely-divided material.

9. A railway covered hopped car for pneumatically unloading finely-divided material or the like and adapted to withstand a positive internal pressure comprising, a side sill extending along each side of the car for substantially the entire length thereof, a shell secured between the side sills, an end bulkhead adjacent each end of the shell, a plurality of transverse partitions spaced along the length of the shell and dividing the car transversely into a plurality of hopper compartments, a bottom hopper outlet structure for each hopper compartment secured between the side sills generally centrally of the width of the car into which the finely-divided material flows for unloading, a reinforcing member extending along the interior surface of said shell adjacent each of said transverse partitions and following the inner contour of the shell in a vertical plane from a position adjacent one side sill to a position adjacent the other side sill, at least one of the reinforcing members being a hollow box-shaped member forming a fluid conduit, means to permit pressurizing the interior of the car, a pneumatic conduit connected to each of the bottom outlet structures for pneumatically discharging finely-divided material, said hollow box-shaped member communicating with the interior of the car for sensing the pressure within the car, and a pressure relief valve in fluid communication with the hollow box-shaped member to hold the pressure within the car at a predetermined maximum amount.

10. A railway covered hopper car as set forth in claim 9 wherein a vacuum relief valve is mounted exteriorly of said car in fluid communication with the hollow boxshaped member to prevent a negative pressure within the car below a predetermined amount.

11. A railway covered hopper car for pneumatically unloading finely-divided material or the like and adapted to withstand a positive internal pressure comprising, a side sill extending along each side of the car for substantially the entire length thereof, a shell secured between the side sills, an end bulkhead adjacent each end of the shell, an intermediate side chord member on each outer side of the car extending longitudinally generally the length of the car at a height above the side sills, a plurality of transverse partitions spaced along the length of the shell and dividing the car transversely into a plurality of hopper compartments, a bottom hopper outlet structure for each hopper compartment secured between the side sills generally centrally of the width of the car into which the finely-divided material flows for unloading, each of said partitions extending generally vertically between the chord members and side sills and terminating upwardly generally at said intermediate chord members, at least one hollow reinforcing tie bar extending between opposite sides of said shell at a predetermined position and communicating with atmosphere to form an air escape passage upon failure of the reinforcing member bar, means to permit pressurizing the interior of the car, and a pneumatic conduit connected to each of the bottom outlet structures for pneumatically discharging finely-divided material.

References Cited by the Examiner UNITED STATES PATENTS 1,274,614 8/1918 Sherman 248 2,108,416 2/1938 Smith et al. 105-247 3,152,842 10/1964 Anderson et al 30253 3,194,420 7/1965 Kemp et a1. 30252 EVON C. BLUNK, Primary Examiner.

ANDRES H. NIELSEN, Examiner. 

1. A RAILWAY COVERED HOPPER CAR FOR PNEUMATICALLY UNLOADING FINELY-DIVIDED MATERIAL AND ADAPTED TO WITHSTAND A POSITIVE INTERNAL PRESSURE, COMPRISING AN END STUB CENTER SILL ADJACENT EACH END OF THE CAR, A SIDE SILL EXTENDING ALONG EACH SIDE OF THE CAR FOR SUBSTANTIALLY THE ENTIRE LENGTH THEREOF, AN INTERMEDIATE CHORD MEMBER ON EACH OUTER SIDE OF THE CAR EXTENDING GENERALLY THE LENGTH OF THE CAR IN A DIRECTION GENERALLY PARALLEL TO THE ADJACENT SIDE SILL, EACH OF THE CHORD MEMBERS BEING SPACED ABOVE THE ADJACENT SIDE SILL, A PLURALITY OF TRANSVERSE PARTITIONS SPACED ALONG THE LENGTH OF THE CAR AND DIVIDING THE CAR TRANSVERSELY INTO A PLURALITY OF HOPPER COMPARTMENTS, A LOWER SIDE SHEET ON EACH SIDE OF THE CAR EXTENDING BETWEEN AND SECURED TO THE ADJACENT SIDE SILL AND THE ADJACENT INTERMEDIATE CHORD MEMBER, EACH LOWER SIDE SHEET BEING FLAT AND SLOPING INWARDLY FROM THE ADJACENT CHORD MEMBER TO THE ADJACENT SIDE SILL TO PROVIDE A RELATIVELY SMOOTH SLOPING INNER SURFACE ALONG WHICH THE FINELY-DIVIDED MATERIAL MAY FLOW FOR UNLOADING, A BOTTOM HOPPER OUTLET STRUCTURE FOR EACH HOPPER COMPARTMENT SECURED BETWEEN THE SIDE SILLS GENERALLY CENTRALLY OF THE WIDTH OF THE CAR INTO WHICH THE FINELY-DIVIDED MATERIAL FLOWS FOR UNLOADING, SAID BOTTOM OUTLET STRUCTURE HAVING OPPOSED SIDE OUTLET SLOPE SHEETS SECURED TO THE ADJACENT SIDE SILLS AND FORMING A CONTINUATION OF THE SUPERJACENT LOWER SIDE SHEETS, AND AN UPPER SHELL HAVING SPACED LOWER EDGES SECURED TO THE RESPECTIVE ADJACENT INTERMEDIATE CHORD MEMBERS ADJCENT THE UPPER EDGES OF THE RESPECTIVE ADJACENT LOWER SIDE SHEETS, SAID UPPER SHELL BEING ARCUATE WITH THE LOWER SIDE SHEETS POSITIONED SUBSTANTIALLY TANGENTIALLY TO THE RADIUS OF THE SHELL ADJACENT THE SIDE SHEETS WHEREBY FORCES ARE TRANSMITTED FROM THE UPPER SHELL TO THE ADJACENT LOWER SIDE SHEETS, AND A PNEUMATIC CONDUIT CONNECTED TO THE BOTTOM OUTLET STRUCTURES FOR PNEUMATICALLY UNLOADING FINELY-DIVIDED MATERIAL FROM THE RAILWAY CAR. 